Tamping unit for tamping a track

ABSTRACT

A tamping unit ( 5 ) for simultaneously tamping three sleepers ( 6 ) of a track ( 3 ) comprises inner, central and outer tamping tools ( 12, 13 ). The pivot axis ( 17 ) of the inner tamping tool ( 12 ) is positioned lower, with respect to the pivot axis ( 17 ) of the central tamping tool ( 13 ), by a vertically extending distance (a). The longitudinal axes ( 18 ) of the two tamping tines ( 19 ) are positioned, with regard to the two pivot axes ( 17 ) of the inner and central tamping tool ( 12, 13 ), off-center and closer to the pivot axis ( 17 ) of the inner tamping tool ( 12 ). With this, it is possible to also tamp without problems sleepers having a small sleeper crib width.

The invention relates to a tamping unit for simultaneously tamping three sleepers of a track according to the features of the introductory part of claim 1.

A tamping unit of this type is known from U.S. Pat. No. 5,133,263. In order to tamp three sleepers simultaneously, it is necessary to group a larger number of tamping tools tightly together with regard to a longitudinal direction of the machine. However, for the unhindered execution of a squeezing motion for consolidating the ballast, these tamping tools must be sufficiently spaced from one another.

It is the object of the present invention to create a tamping unit of the kind mentioned at the beginning with which it is possible to also tamp tracks having a smaller sleeper spacing.

According to the invention, this object is achieved with a tamping unit of the specified kind by means of the features cited in the characterizing part of claim 1.

By relocating the pivot axes of the inner tamping tools in this way, it becomes possible to arrange the tamping tools even closer together with regard to the longitudinal direction of the machine while, in principle, the already time-tested structural embodiment of the tamping unit can still be largely preserved. It is therefore possible with a tamping unit designed in this way to tamp without problems even tracks having a relatively small sleeper spacing.

Additional advantages of the invention become apparent from the dependent claims and the description of the drawing.

The invention will be described in more detail below with reference to an embodiment represented in the drawing in which

FIG. 1 shows a schematic representation of a tamping machine having a tamping unit for simultaneously tamping three sleepers of a track,

FIG. 2 shows an enlarged view of the tamping unit, and

FIG. 3 shows a schematic representation of tamping tools of the tamping unit.

A tamping machine 1, visible in FIG. 1, comprises a machine frame 4 mobile on a track 3 by means of on-track undercarriages 2. Provided between the on-track undercarriages 2 is a tamping unit 5 which is configured for simultaneously tamping three sleepers 6. For correction of the track position, a track lifting unit 7 as well as a reference system 8 are provided. The tamping machine 1 is mobile in a working direction 10 by means of a motive drive 9.

As visible in FIGS. 2 and 3, the tamping unit 5 is composed of a front tool carrier 11, with regard to the working direction 10, and an immediately adjoining rear tool carrier 11. Each vertically adjustable tool carrier 11 comprises an inner tamping tool 12, a central tamping tool 13 and an outer tamping tool 14, wherein the inner tamping tools 12 are arranged immediately adjacent to one another. The outer tamping tools 14 are spaced furthest from one another, the central tamping tools 13 are arranged in each case between inner and outer tamping tools 13, 14. The tamping tools 12, 13, 14 associated in each case with a tool carrier 11 are connected via squeezing drives 15 to a vibration drive 16 and designed for pivoting in the working direction 10 about pivot axes 17. The tamping tools 12, 13, 14 are equipped with tamping tines 19 having longitudinal axes 18.

Described below is the particular arrangement of the tamping tools 12, 13, 14 and their pivot axes 17, allowing tamping, according to the invention, of tracks 3 having small sleeper distances.

The pivot axis 17 of the inner tamping tool 12 is positioned lower, with respect to the pivot axis 17 of the central tamping tool 13, by a vertical distance a (FIG. 3). The longitudinal axes 18 of the tamping tines 19 are positioned, with regard to the two pivot axes 17 of the inner and central tamping tool 12, 13, off-center and closer to the pivot axis 17 of the inner tamping tool 12. The pivot axes 17 of the inner and central tamping tool 12, 13 are spaced at the same horizontal distance b with respect to a vertical line 21 leading through an axis 20 of the vibration drive 16. The vertical distance a corresponds to approximately 30 to 50% of the horizontal distance b. A lever part 22, situated below the pivot axis 17 and provided for fastening the tamping tine 19, of the inner tamping tool 12 is of shorter length than a lever part 23 of the central tamping tool 13. 

1. A tamping unit (5) for simultaneously tamping three sleepers (6) of a track (3), comprising a front tool carrier—with regard to a working direction (10)—and an immediately adjoining rear tool carrier (11), with each of which is associated a respective vibration drive (16) connected in each case by squeezing drives (15) to an inner tamping tool (12)—adjoining the adjacent tool carrier (11)—and to an outer tamping tool (14), spaced from the adjacent tool carrier (11), as well as to a central tamping tool (13) positioned between inner and outer tamping tool (12, 14), wherein the tamping tools (12, 14) are mounted on the tool carrier (11) in each case for pivoting in the working direction (10) about a pivot axis (17) and are connected to a tamping tine (19) having a longitudinal axis (18), comprising the following features: a) the pivot axis (17) of the inner tamping tool (12) is positioned lower, with respect to the pivot axis (17) of the central tamping tool (13), by a vertically extending distance (a), and b) the longitudinal axes (18) of the two tamping tines (19) are positioned, with regard to the two pivot axes (17) of the inner and central tamping tool (12, 13), offcenter and closer to the pivot axis (17) of the inner tamping tool (12).
 2. A tamping unit according to claim 1, wherein the pivot axes (17) of the inner and central tamping tool (12, 13) are spaced at the same horizontal distance (b) with respect to a vertical line (21) leading through an axis (20) of the vibration drive (16).
 3. A tamping unit according to claim 2, wherein the vertical distance (a) corresponds to approximately 30 to 50% of the horizontal distance (b).
 4. A tamping unit according to claim 1, wherein a lever part (22), situated below the pivot axis (17) and provided for fastening the tamping tine (19), of the inner tamping tool (12) is of shorter length than a lever part (23), situated below the pivot axis (17), of the central tamping tool (13). 